In recent days, noise has been regarded as industrial pollution produced in accordance with an industrial development. The noise is produced by various reasons, and methods for removing the noise have been actively researched and studied.
The noise removal can be attained through high absorption and shielding efficiencies according to a frequency of noise resource. In order to attain the high absorption and shielding efficiencies, both structural and material aspects have been researched and studied. As a result of the material research for the noise removal, there are porous materials, fabric materials, and composite materials.
Also, the essentials to the material used for the noise removal are the mechanical property such as high stiffness, and good yield in mass production as well as the soundproofing property such as high absorption and shielding efficiencies.
Up to now, even though the composite material has been researched to be used as the soundproofing composite for the noise removal, the optimal composite material which is capable of satisfying the aforementioned good soundproofing property, high stiffness, and good yield in mass production has not been proposed yet. Thus, there is the continuous need to develop the optimal composite material for satisfying the aforementioned good soundproofing property, high stiffness, and good yield in mass production.